1999 HONDA CIVIC Ground

How To Use This Manual
Troubleshooting Tests
Testing for Voltage Drop
Wires, connectors, and switches are designed
to conduct current wilh a minimum loss of
voltage. A voltage drop of more than one volt
indicates a Droblem.
'1. Place the digital volVohmmeter (DVOM) in
the appropriate DC volts range. Connect
the positive lead to the end of the wire
(or to the connector or switch) closest to
the bafterv.
Connect the negative lead to the other
end of the wire (or the other side of the
connector or switch).
Turn on the components in the circuit.
The DVOM will show the difference
in voltage between the two points. A
difference, or drop, of more than one
volt indicates a oroblem. Check the
circuit for loose, dirty, or bent terminals.
co
Testing lor a Short with a Test Light or DVOM
1. Remove the blown fuse and disconnect
the load.
2. Connect a test light or digital
oltr'ohmmeter
(DVOM), switched to the appropnare DC
volts range, across the tuse lerminals to
make sure voltage is present. You might
have to turn the ignition switch to ON:
check the schematic to see.
<-s80RT TOGFOUNO
Disconnecl lheload here.
Beginning near the luse box, wiggle the
harness. Continue this at convenient ooints
about six inches apart while watching the
test light or DVOM.
Where the test light goes off, or the DVOM
voltage drops to zero, there is a short to
ground in the wiring near that point.
NOTE: Always use a DVOM on high
impedance circuits. A test light may not
glow (even with battery voltage present).
3''
ffito.'"o'o
.t.
TEST LIGHTolDVOM

Testing for a Short with a Sell-Powered
Test Light or DVOM
1. Remove the blown fuse and disconnect
the battery and load.
2. Connect one lead of a self-powered test
light or digital volUohmmeter (DVOM)
(switched to the lowest "OHMS" range) to
the fuse terminal on the load side.
Dlsconnect the batlery.
FUSEBOXRemove the fuse.
<- ssoRr rociouNo
Dlsconnect theload here.
.)"'
r| SOLENOID
Connect the other lead to a known
good ground.
Beginning near the fuse box, wiggle the
harness. Continue this at convenient
points about six inches apart while
watching the test light or DVOM.
lf the self-powered test light goes on or
the DVOM displays a low reading or no
reading (zero), there is a short to ground
in the wiring near that Point.
SELF.POWEREDTEST LIGHTo1DVOM
4.
5.
Testing tor a Short with a Short Circuit
Locator (Short Finder)
1 . Remove the blown fuse. Leave the
battery connected.
2. Connect the short finder across the battery
terminals and the load (component) side of
the fuse terminal.
SATTERY
SHORTFINOER
FUSEBOX
PULSINGMAGNETICFIELD \
NOPUISING
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...unilltheneedle slopsmoving.SHOFTTGFOUNO'llt
No --tPULS|NG z
MAGNETTC IFIELD ISoLENOTO
3. Close all switches in the circuil
you're testing. (co,f,O
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Ground-to-Components I ndex
f.,lONOTE: All ground wires are BLK unless otherwise noted.
GroundPageComponents or Circuit Grounded
Battery (BLKYEL)
Steering pump bracket
t+-rg ITransmission housing
l
G101
(-1)
G101
(-2)
14-2
and
14-3
ano
14-1
Powertrain or engine control module (PG1 and pG2 are BLK: LG1 and LG2 are
BRN/BLK), EGR control solenoid valve (CW, EGR valve and lift sensor (Dt6yS enginewith M,/T), Engine coolant temperature switch, pGM-Fl main relay, power steeringpressure switch (USA), Primary HO2S (D16Y5 engine with l\/,/T), Vehicle speed sensor,VTEC pressure switch (D16Y5/D16Y8 engines), CKF sensor (BRN/BLK), Transmission
control module (CYf) (Pc1 is BLK: LG1 is BRN/BLK)
Shielding betvveen the PCM or ECM and these components (all have BRN/BLK wires):
CKF sensor, TDC/CKP/CYP sensor. Primary and secondary heated oxygen sensors.
Knock sensor (CWDl6YB engine), Mainshaft speed sensor (AiT except CVT),
I Countershaft speed sensor (A/T except CVf)
Shielding between the TCM and these components (CVT) (all have BRN/BLK wires):
Drive pulley speed sensor, Driven pulley speed sensor, Secondary gear shaft
speed sensor
Powertrain or engine control module (PG1 and pG2 are BLK; LG1 and LGz are
BRN/BLK), EGR control solenoid valve (D16Y5 engine), EGR valve (Dt685), Engine
coolant temperature switch, Fuel pressure regulator shut-off solenoid valve (D1685),
PGM-FI main relay, Power steering pressure switch (USA), Vehicle speed sensor, VTECpressure switch (All except D16Y7 engine), CKF sensor (A

except 81642) (BRN/BLK)
Shielding between the PCM or ECM and these components (all have BRN/BLK wires):
CKF sensor, TDC/CKP/CYP sensor, Primary and secondary heated oxygen sensors,
Knock sensor (All except D16Y7 engine), i/ainshaft speed sensor (Arf except CW),
Countershaft speed sensor (A,/T except CVf), Drive pulley speed sensor (CW), Drivenpulley speed sensor (CVT), Secondary gear shaft speed sensor (CVf)
I Badiator fan motor, Right front parking/turn signat tight, Right headtight
G20214-4I Cruise control actuator, Left front parking/turn signal lights, Left headlight, Rear window
I washer motor, Windshield washer motor, Washer fluid level switch (,99-'00 Canada)
G401| +-o
and
14-7
Accessory power socket, Brake fluid level switch, Clutch interlock switch (M/T), Clutchswitch (lillT with cruise/D16Y5 engine with MfD, Combination wiper switch (Z wires),
Cruise control main switch, Cruise control unit, Dash lights brightness controller, Data
link connector, Daytime running lights control unit (Canada), Gauge assembly, Horn('96-'97 models), Integrated control unit, Interlock control unit (ArI), Keyless door lock
control unit ('99-'00 models with keyless), Moonroof close and open relays, Moonroof
switch, Park pin switch (A/r), Power window relay, Rear window defogger relay, Rear
window defogger switch ('96-'98 models), Steering lock, Stereo radio tuner (,96-,98
USA: LX, EX, and HX), Turn signal/hazard relay, Windshield wiper motor.....plus
everything grounded through G402
6-6

Ground
G402
Components or Clrcult Grounded
Arr gear position switch, ABS control unit (3 wires), Blower motor high relay ('99-'00
models), Blower motor relay, ELD unit, Heater Jan switch ('96-'98 models), Heater
control panel, Mode control motor ('96.98 models), Power transistor ('99-'00 models),
Service check connector....plus everything grounded through G401
| 14-13 | ABS pump motor
1l-9 i Stereo radio tuner ('96-'98 models), Audio unit ('99-'00 models)
Drivsr's door lock actuator, Driver's door lock switch, Drivefs window motor' Left mirror
defogger, Pow€r window master switch (2 wires), Power door lock control unit (all
except '99-'00 with keyless), Power mirror switch
G55214-9 i Driver's s€at belt switch, Fuel pump, Fuel tank unit, Right mkror defogger
G601
(Hatch-
back)
14-12 iLeft and right back-up lights, Left and right brake lighvtail lights, Lefl and right rear
turn signal lights, Left and right tail lights....plus eveMhing grounded through G761
G601 I 14-10
(All Coupesl
ano
(96198
S6dans)
High mount brake light, Left and right back-up lights, Left and right inner brake lighv
taiilights, Lett and right license plale lights, Lett and right outer brak€ lighvtail lights'
Left and right rear turn signal lights, Rear window deJogger, Trunk latch switch
G601
(99-'oo
Sedans)
G602
('ss-'00
Sedans)
G761
(Hatch-
back)
G771
(Hatch-
back)
14-11
14-12 i
High mount brake light, Left and right back-up lights, Left and right brake lighvouter
taillights, Left and right inner taillight, Left and right rear turn signal light' Rear window
deJogger (GX), Trunk latch switch
Window antenna coil
Hatch latch switch ('98-'00 models), High mount brake light' Left and right license plate
lights, Rear window wiper motor...plus everything grounded through G601
Rear window defogger
14-13 i SRS unit (2 wires)
*1 = All '96-98 models €xcept Dl685, '99100 D16Y5 with M/T*2 = '98 D1685, all '99-'00 models except Dl6Y5 with M/T
e7

Ground Distribution
- Gl01 (All '96-'98 models except D1685; '99100 D16y5 with M/T)
NOTE: Wires shown without color codes
:--- CVr --' D16y5/
i rnlts_ ' ._ 016y8,MISSION',englnes
: CONTROL ' PGM.FI :: MODULE i UAIH ; VTEC, TTCM) ; RELAY . PRESSURE' Paae 39-5 ' Paoe 23 ' SWITCHI pHdro et ' n 6roao ' Page 23-4I vtEw 69 | vtEw 1a ' pHoro 44' r---.t ' r-1 I i-r
POWERTRAIN orENGINE CONTROLMODULE (PCM or ECM)Page 23-3PHATO 86vlEw 7a; r---1 ;r-1 , r, I t,t | ,l
: I t:t | :l, L---J, L-J ' L-, A26Y A13Y , 3,2
i T T: I I
I I, I t,,-I T T: T i
: I t:--I-. :
i I \li:; -4, ;!-------------l-i '
'lF;% :21 ,vlEw 28 ;
_ - t\4/T -
PRIMARYHEATEDOXYGENSENSOR(H02S)Page 23-13
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14
o---1\
I

Ground Distribution
- Gl01 ('98 Dl685;All '99-'00 models except D16YS with M/T)
NOTE: Wires shown without color codes are black.
01685/_ D16Y5/ -.016Y8engrnes
.__-;,#'-_,--', engrne ;
, wEc: PRESSURE '
, swtTcH :I Page24-4 iI PHOTO 150: r -'l
:t | :
:l | :,L-J.
FUELPRESSUREREGULATOR ENGINESHUT.OFF COOLANTSOLENOID TEMPERATUREVALVE SWTTCHPage 25-1 Page 63PHOIO 143 PHOTA 33r-1F-.|
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lltlL-J L-J
POWERTRAIN olENGINE CONTROLMODULE (PCM or ECM)Page 24-3 ot 25-3PHOTO 86
----:y4
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PGi,|.FIMAINRELAYPage 24ol 25
vlEw 18
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3Y'I'I
excaptD1685
VEHICLESPEEDSENSOR(vss)Page 336FN/ELKERll/EIKcl01PHOTO 21PHOTO 142(o1685)vtEw 28
ct16Cferml-nals8n 4)
FltaFt( vttw 39t- .''iiti ' " D1685/D16Y5 engrnes ---'
t2
. ENGINE : :
i 933'?il-; i 5"T,Yf,*' 33i,"o, i
i lgfft" i I S.ir1".l^ soL€NorD :' Pase 63 : : ;;;;; - pase 24.i :' PHOTO 63 | | VtEWlO pHOIa124 ;, r-1 | , F-.t r-.r
:l | ;:l | ! | :;t | :,t | | | ;
j,f
ii T.__.,|,,,,,.
j
--
----- --l i otoas I Dr6y5 :
:------.1.--------.
14-2
o-----J

Ground Distributiofl (cont'd)
- G201 andG202
NOTE: Wires shown wrthout color codes are black.
RIGHTHEAD.LIGHTPage110-12
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110-9
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LEFT FRONTPARKING/TURNSIGNALLIGHTPages 110-2,1 10-7, and110-9
()
WIND.SHIELDWASHERMOTORPage 91PHOTA 3
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REARwtNDowWASHERMOTORPage 92
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c205
RIGHT FRONTPARKING/TURNStcNAL RADIATORLIGHT FANPaoes 110-2, MOTOR11d-7, and Page 63
'99-'00
.- Canada -l
i wnsxen i cnurse, FLUID ; CONTROL' LEVEL . ACTUATOR' SWITCH I paoe 34-2; Page 80-3 i eu6ro re'f-1 ' f-1
2Y2
c211
14-4
I'G201'Lv G2o2

Ground Distributioh (conrd)
)
- G401
NOTE:
To G402on page14-5.
WINOSHIELOWIPERMOTORPage 91-1
DAYTIMERUNNINGLIGHTS
99.!rRoL cLUrcHuNr I swtTcH:?99^ Pases 23-5and 34-3vtEw 66 PHA|A 55
I
I
INJECTORCONTROLMODULEPage 25-1
I
I
3
. Wires shown without color codes are black.
o On Coupe and Sedan models, G401 is represented by ring terminals.
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INTER.LOCK6611p99 PARKUN|T PINpaoe j38 SWITCHor ige_t Page 138PHoro6s of 138-1vtEw 26 PHOfO /7r-1 r-'t
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CLUTCHINTER-LOCKSWITCHPage 21-2
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t
M/T with 01685Cruise/D16Y5enginewith M/T
BRAKEFLUIDLEVELswtTcHPage 71ot 71-1
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DOOR LOCK .CONTROLSTEERINGLOCKPage /3
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UNITPage 130-12 ;
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models
RNte 40
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(
I
I czor
l'i1l?,
'97 mo
HORNPage 4
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I
NFnl
s 9c.Plv'
BLK/RED
t
IJ;--
',f-l
DATA LINKCONNECTOR(DLC)Pages 23-4,24-4,25 4,44-1, and 47
30
14-6
G401